Clavicle

the clavicle or collarbone is a long bone that serves as a strut between the scapula and the sternum. It is the only long bone in the body that lies horizontally. It makes up part of the shoulder and the pectoral girdle, and is palpable in all people; in people who have less fat in this region, the location of the bone is clearly visible, as it creates a bulge in the skin. It receives its name from the Latin: clavicula (“little key”) because the bone rotates along its axis like a key when the shoulder is abducted.